cooling afterrunning period is initiated; this lasts approx. 90 s.
If there is a malfunction, the heater will not switch the fuel pump on for safety reasons.
In order to protect the batteries, the heater has an undervoltage trip. In order to
ensure that the batteries are recharged while travelling, follow this rule of thumb: the
travelling time should be greater than or equal to the preheating time.
Use of residual heat
–
Activation:
Use of residual heat is only activated when the heater is switched on. This is a fully auto-
matic function that is activated when the engine is warm; it is used to conserve energy.
Every time the heater is switched on, before the heating process, the heater checks the
coolant temperature. If the coolant temperature is above 60°C, use of residual heat is auto-
matically activated. When use of residual heat is activated, the coolant pump for the heater
and the vehicle blower are automatically actuated.
–
Deactivation:
Deactivation of the use of residual heat is carried out automatically by the heater control
unit.
Control elements
The Thermo Pro 90 HDD can be fitted with various control elements:
2
– Switch (example 1 )
– MultiControl or SmartControl (example 2 )
A combination of control elements is also possible.
The control elements confirm when the heaters are switched on. A detailed description of each
control element is enclosed with the respective control element.
Vehicles with ADR equipment
In ADR vehicles, it is not possible to set a preselection time. The display shows the remaining
operation time while the heater is in operation. The time of day can be set.
Malfunctions and troubleshooting
In the event of a malfunction, a malfunction can be displayed, depending on the type of
control elements.